Power-operated massagers are often used to treat muscle tension and fatigue. Massagers that exert a percussive effect on the body are preferred over massagers which generate a rubbing action, since the latter type of massager can cause irritation or other discomfort to the recipient.
U.S. Pat. No. 4,730,605 issued to Noble et al. discloses one such percussive massager. The massager has a casing with two handles, and is intended for two-handed operation. U.S. Pat. No. 5,716,332 issued to Noble discloses a similar percussive massager that is designed so as to be capable of use for self massage. In both massagers, the massage head is coupled to a base structure for pivotal rocking movement about a pivot axis for exerting a percussive massage effect.
More particularly, the massagers referenced above each include a weight is affixed to the drive shaft of the motor. The weight has a vertical arm attached eccentrically thereto, such that rotation of the drive shaft causes the vertical arm to move axially. The vertical arm is coupled to a first massage formation, which is in turn connected to a second massage formation by a rigid surface. Movement of the vertical arm causes the first massage formation to be moved upwardly and downwardly, and in turn causes the second massage formation to be moved in the opposite direction about a central pivot. Unfortunately, this design has the disadvantage that movement of the first and second massage formations are both controlled by the same vertical arm and are not moved independently. Consequently, if the vertical arm breaks, the movement of both massage formations ceases.